Lead Block inside 52' US-type Trailer Experiement

In summary, if a lead block weighing approximately 2.81 million pounds was inserted into a standard refrigerated cargo trailer weighing only 50,000 pounds, the tires would burst and most of the undercarriage would be crushed into the pavement. This would cause significant damage to the trailer, tractor, and potentially the road. The cost of repairing this damage would be substantial, likely exceeding the potential fine for overloading the trailer.
  • #1
OctaneMaestro
11
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Can someone calculate the weight of the object and what would most likely happen in the following experiment that I have always been curious about:

Imagine you have a brand new 52-foot standard refrigerated cargo trailer mounted on a brand new standard heavy duty sleep cab tractor (i.e., an "18-wheeler" or "tractor trailer). Assume a lead block that is 1" smaller in every dimension than the opening of the rear of the truck and also 1" shorter than the front to back length of the interior of the trailer. I use 1" inch less so no one says it would bind against the sides and it could not be inserted, but feel free to adjust that dimension slightly if it helps. Assume that this enormous lead block before being inserted into the trailer is laying on type of a hypothetical forklift's fork that is hypothetically long enough to be able to hold this long block of lead. And assume the forklift has enough counterbalance not to tip over from the weight of the block (I realize this probably doesn't exist). Also assume the forklift has a "pusher" behind its fork that can push this lead block off its fork. Also assume that the forks are not not thicker than one inch tall (so they will not bind against the truck opening when carrying this one inch lead block.

Assume the truck is located on aircraft runway quality concrete that will support millions of pounds. Now here's the question:

What would happen to the truck the instant this lead block is inserted into the truck and it begins to handle its load on its own? Would the tires instantly all burst? Would it crack the concrete? Would it not just instantly burst the tires but would crush the entire undercarriage of the truck's drive wheels and trailer wheels/axles and everything else in the undercarriage and just be flush with the ground? I'm really curious!
 
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  • #2
A lead block the size you're describing (appromiately 100"x110"x52') would weigh around 2.81 million pounds. Considering a trailer of the 100"x110"x52' variety will have a load capacity of around 50,000lbs, that means your block weighs 52 times more than the trailer's carrying capacity.

It would burst the tires and likely crush most of the undercarriage into the pavement.
 
  • #3
Mech_Engineer said:
A lead block the size you're describing (appromiately 100"x110"x52') would weigh around 2.81 million pounds. Considering a trailer of the 100"x110"x52' variety will have a load capacity of around 50,000lbs, that means your block weighs 52 times more than the trailer's carrying capacity.

It would burst the tires and likely crush most of the undercarriage into the pavement.

Thanks. It would be amazing to see that happen. Do you know for certain that the tires would burst instantly upon the bottom portion of the rims impacting the pavement (imagine freezeframing the entire downward motion of the trailer at that moment) or are you saying they would burst split seconds later as the entire trailer crushed the undercarriage into the pavement?

Secondly, would there be any "pancake" left visible of the undercarriage, considering some of it is solid steel (like the axles) or do you think it would be pulverized or simply pushed upward into the soft lead that crushed it making it invisible? Also would the lead flatten out bursting the side of the trailer because of its softness and mass upon impact with the pavement, or would it be contained in the trailer box?
 
  • #4
Dude, who cares? The trailer would be history.
 
  • #5
Mech_Engineer said:
Dude, who cares? The trailer would be history.

I care. Other people probably are interested too. It's an interesting visual, especially because I think in industry people commonly way overload trailers. Even if this exact extreme example is never attempted, it's a relevant study to see what happens when users overburden mechanical devices.
 
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  • #6
That would generate an average weight of 420lbs. per square inch - over every square inch of the trailer's floor and undercarriage...
 
  • #7
Interesting scenario.

Realizing the high cost of osmium and uranium, (let alone other dense materials) 2.8 million pounds of lead (plus the weight of the trailer and tractor) would be the theoretical maximum overload even remotely feasible the Department of Transportation Vehicle Enforcement officers could ever hope to snag.

As I recall, the fine rates in most states is $.10/lb, so the overweight fine would be approaching $300,000. Considering the damage this load would do to highways, bridges, and viaducts, this is actually a 'deal'.
 
  • #8
And the gas consumption!
 
  • #9
DaveC426913 said:
And the gas consumption!

tasp77 said:
Interesting scenario.

Realizing the high cost of osmium and uranium, (let alone other dense materials) 2.8 million pounds of lead (plus the weight of the trailer and tractor) would be the theoretical maximum overload even remotely feasible the Department of Transportation Vehicle Enforcement officers could ever hope to snag.

As I recall, the fine rates in most states is $.10/lb, so the overweight fine would be approaching $300,000. Considering the damage this load would do to highways, bridges, and viaducts, this is actually a 'deal'.

Mmyess, interesting indeed. Let's assume it didn't crush the trailer immediately as the previous gentleman predicted. And assume further that the driver of said tractor-trailer 18-wheeler combination put in a full 8-hour work day pulling this rig at highway speeds. How much damage in dollars ($) do you think he would cause in one day? $175 billion?
 
  • #10
OctaneMaestro said:
Mmyess, interesting indeed. Let's assume it didn't crush the trailer immediately as the previous gentleman predicted. And assume further that the driver of said tractor-trailer 18-wheeler combination put in a full 8-hour work day pulling this rig at highway speeds. How much damage in dollars ($) do you think he would cause in one day? $175 billion?

No way. First of all, gigantic loads rarely travel more than about 50 mph, so if you say he was going 50mph the whole time (which of course would be impossible since the tires would explode and the trailer would crush) he would only travel about 400 miles assuming no stops. It might cost a couple million to repair that much road asuming it was badly damaged.
 
  • #11
Mech_Engineer said:
No way. First of all, gigantic loads rarely travel more than about 50 mph, so if you say he was going 50mph the whole time (which of course would be impossible since the tires would explode and the trailer would crush) he would only travel about 400 miles assuming no stops. It might cost a couple million to repair that much road asuming it was badly damaged.

I don't understand the purpose of imagining how much damage a trailer could do over its journey if there can be no journey.
Q: "If it didn't crush the chassis, how much would it crush the road under the chassis?"
A; "Well none, since you've invoked some sort of magic in your scenario but have not told us what the magic is."

No, the amount of damage this trailer can do is limited to its initial parking spot - an area of ground approximately 52'x110". Full stop.
 

1. What is the purpose of the "Lead Block inside 52' US-type Trailer Experiment?"

The purpose of this experiment is to study the effects of placing a lead block inside a 52' US-type trailer on the overall weight distribution and stability of the trailer while in motion.

2. How is the lead block positioned inside the trailer?

The lead block is placed in the center of the trailer, secured to the floor using straps or bolts to prevent movement during the experiment.

3. What are the expected results of the experiment?

The expected results of the experiment include a shift in the trailer's center of gravity and changes in the weight distribution, which may affect the trailer's handling and stability while in motion.

4. What safety precautions are taken during the experiment?

Safety precautions include ensuring that the lead block is properly secured and that the trailer is not overloaded beyond its weight capacity. The experiment is also conducted in a controlled environment with safety measures in place to prevent accidents.

5. How will the data collected from this experiment be used?

The data collected will be analyzed to determine the effects of the lead block on the trailer's weight distribution and stability. This information can be used to improve the design and safety of trailers in the future.

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